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I've been doing some thinking, and began to wonder: What observations have led us to the conclusion that ‘energy can neither be created nor destroyed’?
Essentially, this means that the big bang supplied our universe with all the matter that currently exist in it.
My question is, if this were untrue for some reason (despite what math tells us) - and there were more ‘atoms’, ‘quarks’ or ‘bits’ being added to the system, how would we tell? What would that look like?
What experiment would be used to detect ‘more matter’ existing now than during the big bang?
Is this simply a matter of creating instruments that measure more accurately, or would some clever experiment need to be devised?
I've read several answers on this and other sites that explain the law of conservation of energy, but none that nail the hypothetical question above.